Standards for quantitative assessments by coronary computed tomography angiography (CCTA): An expert consensus document of the society of cardiovascular computed tomography (SCCT).

In current clinical practice, qualitative or semi-quantitative measures are primarily used to report coronary artery disease on cardiac CT. With advancements in cardiac CT technology and automated post-processing tools, quantitative measures of coronary disease severity have become more broadly available. Quantitative coronary CT angiography has great potential value for clinical management of patients, but also for research. This document aims to provide definitions and standards for the performance and reporting of quantitative measures of coronary artery disease by cardiac CT.

Embolization of Perforated Coronary Artery with a Fragment of Balloon Catheter (Cut Balloon Technique)-Multicenter Study.

BACKGROUND: Iatrogenic distal coronary artery perforation can be a life-threatening complication. While there are different dedicated devices for the embolization of distal perforations, there are scarce data about the embolization using the fragmented balloon catheter, the so-called cut balloon technique (CBT). METHODS: We included consecutive patients with distal coronary perforations treated with CBT in four cardiac centers between 2017 and 2023. Clinical, angiographic and procedural characteristics as well as in-hospital outcomes were recorded. RESULTS: Twenty-six patients (68% men, mean age: 71 ± 10.6 years) with 25 distal coronary perforations and one septal collateral perforation were included. Eleven patients (42%) had elective percutaneous coronary intervention, while fifteen patients (58%) were treated for acute coronary syndrome. The site of perforation was most frequently distributed in the left anterior descending artery (40%), followed by the circumflex artery (28%) and right coronary artery (24%). The diameter of balloons for CBT ranged from 1.5 to 4.0 mm, with most balloons (76%) being either 2.0 or 2.5 mm in diameter. Most balloons (88%) were previously used for lesion predilatation. The numbers of cut balloons needed to seal the perforation were 1, 2 and ≥3 in 48%, 20% and 32% of cases, respectively. The in-hospital prognosis was favorable, with cardiac tamponade requiring pericardiocentesis in only four (16%) patients. Neither emergency surgery nor cardiac death occurred. CONCLUSIONS: CBT is a safe, efficient and easy-to-implement technique for the embolization of coronary perforations. Most distal coronary perforations can be sealed with one or two fragments of cut balloons, obviating the need for additional devices.

Computed tomography perfusion and angiography in patients with chronic total occlusion undergoing percutaneous coronary intervention.

BACKGROUND AND AIMS: Myocardial perfusion imaging (MPI) and anatomical imaging with coronary computed tomography angiography (CCTA) can play an important role in the preprocedural planning of a chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We aimed to establish the feasibility of a novel dynamic computed tomography perfusion (CTP) analysis for the assessment of myocardial perfusion before and after a successful recanalization of CTO in patients undergoing CCTA as part of a standard preprocedural workup. METHODS: In a prospective observational study symptomatic patients underwent dynamic CTP on a dual-source CT scanner both before and 3 months after successful CTO PCI. RESULTS: Twenty-seven patients completed the study (63 ± 8 years old, 78% male). Following successful CTO PCI, there was a significant reduction in the ischemic burden (5 [5-7] versus 1 [0-2] segments, p < 0.001), and improvement in myocardial blood flow (85.3 [71.7-94.1] versus 134.6 [123.8-156.9] mL/min, p < 0.001) resulting in an increase in the relative flow reserve (0.49 [0.41-0.57] versus 0.88 [0.74-0.95], p < 0.001). CONCLUSIONS: CTP emerges as a robust and safe method for MPI in CTO patients. The single imaging session assessment of both coronary anatomy and perfusion with CT lends itself to precise disease phenotyping in the challenging population of CTO patients.

Machine learning for prediction of all-cause mortality after transcatheter aortic valve implantation.

AIMS: Prediction of adverse events in mid-term follow-up after transcatheter aortic valve implantation (TAVI) is challenging. We sought to develop and validate a machine learning model for prediction of 1-year all-cause mortality in patients who underwent TAVI and were discharged following the index procedure. METHODS AND RESULTS: The model was developed on data of patients who underwent TAVI at a high-volume centre between January 2013 and March 2019. Machine learning by extreme gradient boosting was trained and tested with repeated 10-fold hold-out testing using 34 pre- and 25 peri-procedural clinical variables. External validation was performed on unseen data from two other independent high-volume TAVI centres. Six hundred four patients (43% men, 81 ± 5 years old, EuroSCORE II 4.8 [3.0-6.3]%) in the derivation and 823 patients (46% men, 82 ± 5 years old, EuroSCORE II 4.7 [2.9-6.0]%) in the validation cohort underwent TAVI and were discharged home following the index procedure. Over the 12 months of follow-up, 68 (11%) and 95 (12%) subjects died in the derivation and validation cohorts, respectively. In external validation, the machine learning model had an area under the receiver-operator curve of 0.82 (0.78-0.87) for prediction of 1-year all-cause mortality following hospital discharge after TAVI, which was superior to pre- and peri-procedural clinical variables including age 0.52 (0.46-0.59) and the EuroSCORE II 0.57 (0.51-0.64), P < 0.001 for a difference. CONCLUSION: Machine learning based on readily available clinical data allows accurate prediction of 1-year all-cause mortality following a successful TAVI.

Infarct-related artery and long-term mortality following recurrent ST-segment elevation myocardial infarction. Insights from a Polish nationwide registry.

BACKGROUND: Recurrent ST-segment elevation myocardial infarction (rSTEMI) can be attributed to the same (target-vessel, TV-rSTEMI) or different culprit vessel (non-target, nonTV-rSTEMI) compared with the first infarction. We hypothesized that long-term mortality after rSTEMI depends on the infarct-related artery (the same or different compared with the first STEMI). METHODS: Using the Polish Registry of Acute Coronary Syndromes (PL-ACS) we retrospectively identified survivors of first STEMI treated with PCI who experienced rSTEMI. We divided rSTEMI into TV-rSTEMI and nonTV-rSTEMI. We compared clinical, angiographic, and procedural characteristics and utilized propensity score matching to adjust for baseline differences. Primary outcome was 1-, 3- and 5-year all-cause mortality. RESULTS: Between 2003 and 2019 a total of 3,411 patients (mean age 63.7 years, 76% male) had rSTEMI, of whom 1,916 (56%) had TV-rSTEMI and 1,495 (44%) had nonTV-rSTEMI. Median time since first infarction was 716 days (100, 1,807). Patients with nonTV-rSTEMI had higher body mass index (27.2 vs 26.7 kg/m2, P = .041), more arterial hypertension (77.4 vs 73.7%, P = .015) and atrial fibrillation (4.8 vs 3.3%, P = .02), and lower left ventricular ejection fraction (43 [35, 50] vs 45 [38, 50]%, P <.001) compared with TV-rSTEMI. On coronary angiography nonTV-rSTEMI more frequently presented with Thrombolysis In Myocardial Infarction >1 flow (25.8 vs 15.7%, P < .001), multivessel disease (51.9 vs 40.8%, P =.002), culprit lesion located in circumflex artery (22.6 vs 5.6%, P < .001), and more frequently underwent stenting (88.8 vs 76.1%, P < .001) compared with TV-rSTEMI. There was no difference in unadjusted 1-, 3- and 5-year mortality between nonTV-rSTEMI and TV-rSTEMI. After propensity score analysis, 807 well-matched pairs of patients were selected. Adjusted 1-, 3- and 5-year mortality remained similar between nonTV-rSTEMI and TV-rSTEMI (14.7 vs 14.4%, P = .88; 23.6 vs 23.1%, P = .81; 30.0 vs 32.0%, P = .50 respectively). CONCLUSIONS: Our study shows overall low frequency of rSTEMI. Patients with nonTV-rSTEMI have different clinical and angiographic characteristics compared with TV-rSTEMI. No long-term mortality difference was observed between both groups.

Computed Tomography Angiography-Derived Scores for Prediction of Chronic Total Occlusion Percutaneous Coronary Intervention Using the Hybrid Algorithm.

Whereas coronary computed tomography angiography (CCTA) exceeds invasive angiography for predicting the procedural outcome of chronic total occlusion (CTO) percutaneous coronary intervention (PCI), CCTA-derived scores have never been validated in the hybrid CTO PCI population. In this single-center, retrospective, observational study, we included 108 consecutive patients with 110 CTO lesions and preprocedural CCTA who underwent hybrid CTO PCI to assess the diagnostic accuracy of CCTA-derived scoring systems. Successful guidewire crossing within 30 min was set as the primary endpoint. The secondary endpoints were final procedural success and the need for using any non-antegrade wiring (AW) strategy within the hybrid algorithm. Time-efficient guidewire crossing and final procedural success were achieved in 53.6% and 89.1% of lesions, respectively, while in 36.4% of the procedures, any non-AW strategy was applied. The median J-CTO score was 1 (interquartile range (IQR): 0, 2), while the CT-RECTOR, KCCT, J-CTOCCTA, and RECHARGECCTA scores were 2 (IQR: 1, 3), 3 (IQR: 2, 5), 1 (IQR: 0, 3), and 2 (IQR: 1, 3), respectively. All scores were significantly higher in the lesions with failed versus successful time-efficient guidewire crossing. Although all of the CCTA-derived scores had numerically higher predictive values than the angiographic J-CTO score, no significant differences were noted between the scores in any of the analyzed study endpoints. High sensitivity of the CT-RECTOR and RECHARGECCTA scores (both 89.8%) for predicting successful guidewire crossing within 30 min, and high sensitivity (90.8%) of the KCCT score for predicting final procedural success, were noted. CCTA-derived scoring systems are accurate, noninvasive tools for the prediction of the procedural outcome of hybrid CTO PCI, and may aid in identifying the need for use of the hybrid algorithm.

Optical coherence tomography in coronary atherosclerosis assessment and intervention.

Since optical coherence tomography (OCT) was first performed in humans two decades ago, this imaging modality has been widely adopted in research on coronary atherosclerosis and adopted clinically for the optimization of percutaneous coronary intervention. In the past 10 years, substantial advances have been made in the understanding of in vivo vascular biology using OCT. Identification by OCT of culprit plaque pathology could potentially lead to a major shift in the management of patients with acute coronary syndromes. Detection by OCT of healed coronary plaque has been important in our understanding of the mechanisms involved in plaque destabilization and healing with the rapid progression of atherosclerosis. Accurate detection by OCT of sequelae from percutaneous coronary interventions that might be missed by angiography could improve clinical outcomes. In addition, OCT has become an essential diagnostic modality for myocardial infarction with non-obstructive coronary arteries. Insight into neoatherosclerosis from OCT could improve our understanding of the mechanisms of very late stent thrombosis. The appropriate use of OCT depends on accurate interpretation and understanding of the clinical significance of OCT findings. In this Review, we summarize the state of the art in cardiac OCT and facilitate the uniform use of this modality in coronary atherosclerosis. Contributions have been made by clinicians and investigators worldwide with extensive experience in OCT, with the aim that this document will serve as a standard reference for future research and clinical application.

Intravascular Lithotripsy for the Treatment of Stent Underexpansion: The Multicenter IVL-DRAGON Registry.

Background: Whereas the efficacy and safety of intravascular lithotripsy (IVL) have been confirmed in de novo calcified coronary lesions, little is known about its utility in treating stent underexpansion. This study aimed to investigate the impact of IVL in treating stent underexpansion. Methods and Results: Consecutive patients with stent underexpansion treated with IVL entered the multicenter IVL-Dragon Registry. The procedural success (primary efficacy endpoint) was defined as a relative stent expansion >80%. Thirty days device-oriented composite endpoint (DOCE) (defined as a composite of cardiac death, target lesion revascularization, or target vessel myocardial infarction) was the secondary endpoint. A total of 62 patients were enrolled. The primary efficacy endpoint was achieved in 72.6% of patients. Both stent underexpansion 58.5% (47.5−69.7) vs. 11.4% (5.8−20.7), p < 0.001, and the stenotic area 82.6% (72.4−90.8) vs. 21.5% (11.1−37.2), p < 0.001, measured by quantitative coronary angiography improved significantly after IVL. Intravascular imaging confirmed increased stent expansion following IVL from 37.5% (16.0−66.0) to 86.0% (69.2−90.7), p < 0.001, by optical coherence tomography and from 57.0% (31.5−77.2) to 89.0% (85.0−92.0), p = 0.002, by intravascular ultrasound. Secondary endpoint occurred in one (1.6%) patient caused by cardiac death. There was no target lesion revascularization or target vessel myocardial infarction during the 30-day follow-up. Conclusions: In this real-life, largest-to-date analysis of IVL use to manage underexpanded stent, IVL proved to be an effective and safe method for facilitating stent expansion and increasing luminal gain.

Impact of percutaneous coronary intervention of chronic total occlusions on absolute perfusion in remote myocardium.

BACKGROUND: Revascularisation of a chronic total coronary occlusion (CTO) impacts the coronary physiology of the remote myocardial territory. AIMS: This study aimed to evaluate the intrinsic effect of CTO percutaneous coronary intervention (PCI) on changes in absolute perfusion in remote myocardium. METHODS: A total of 164 patients who underwent serial [15O]H2O positron emission tomography (PET) perfusion imaging at baseline and three months after successful single-vessel CTO PCI were included to evaluate changes in hyperaemic myocardial blood flow (hMBF) and coronary flow reserve (CFR) in the remote myocardium supplied by both non-target coronary arteries. RESULTS: Perfusion indices in CTO and remote myocardium showed a positive correlation before (resting MBF: r=0.84, hMBF: r=0.75, and CFR: r=0.77, p<0.01 for all) and after (resting MBF: r=0.87, hMBF: r=0.87, and CFR: r=0.81, p<0.01 for all) CTO PCI. Absolute increases in hMBF and CFR were observed in remote myocardium following CTO revascularisation (from 2.29±0.67 to 2.48±0.75 mL·min-1·g-1 and from 2.48±0.76 to 2.74±0.85, respectively, p<0.01 for both). Improvements in remote myocardial perfusion were largest in patients with a higher increase in hMBF (ß 0.58, 95% CI: 0.48-0.67, p<0.01) and CFR (ß 0.54, 95% CI: 0.44-0.64, p<0.01) in the CTO territory, independent of clinical, angiographic and procedural characteristics. CONCLUSIONS: CTO revascularisation resulted in an increase in remote myocardial perfusion. Furthermore, the quantitative improvement in hMBF and CFR in the CTO territory was independently associated with the absolute perfusion increase in remote myocardial regions. As such, CTO PCI may have a favourable physiologic impact beyond the intended treated myocardium.

DEtection of ProxImal Coronary stenosis in the work-up for Transcatheter aortic valve implantation using CTA (from the DEPICT CTA collaboration).

OBJECTIVES: Computed tomography angiography (CTA) is performed routinely in the work-up for transcatheter aortic valve implantation (TAVI), and could potentially replace invasive coronary angiography (ICA) to rule out left main (LM) and proximal coronary stenosis. The objectives were to assess the diagnostic yield and accuracy of pre-TAVI CTA to detect LM and proximal coronary stenosis of ≥ 50% and ≥ 70% diameter stenosis (DS). METHODS: The DEPICT CTA database consists of individual patient data from four studies with a retrospective design that analyzed the diagnostic accuracy of pre-TAVI CTA to detect coronary stenosis, as compared with ICA. Pooled data were used to assess diagnostic accuracy to detect coronary stenosis in the left main and the three proximal coronary segments on a per-patient and a per-segment level. We included 1060 patients (mean age: 81.5 years, 42.7% male). RESULTS: On ICA, the prevalence of proximal stenosis was 29.0% (≥ 50% DS) and 15.7% (≥ 70% DS). Pre-TAVI CTA ruled out ≥ 50% DS in 51.6% of patients with a sensitivity of 96.4%, specificity of 71.2%, PPV of 57.7%, and NPV of 98.0%. For ≥ 70% DS, pre-TAVI CTA ruled out stenosis in 70.0% of patients with a sensitivity of 96.7%, specificity of 87.5%, PPV of 66.9%, and NPV of 99.0%. CONCLUSION: CTA provides high diagnostic accuracy to rule out LM and proximal coronary stenosis in patients undergoing work-up for TAVI. Clinical application of CTA as a gatekeeper for ICA would reduce the need for ICA in 52% or 70% of patients, using a threshold of ≥ 50% or ≥ 70% DS, respectively. KEY POINTS: • Clinical application of CTA as a gatekeeper for ICA would reduce the need for ICA in 52% or 70% of TAVI patients, using a threshold of ≥ 50% or ≥ 70% diameter stenosis. • The diagnostic accuracy of CTA to exclude proximal coronary stenosis in these patients is high, with a sensitivity of 96.4% and NPV of 98.0% for a threshold of ≥ 50%, and a sensitivity of 96.7% and NPV of 99.0% for a threshold of ≥ 70% diameter stenosis. • Atrial fibrillation and heart rate did not significantly affect sensitivity and NPV. However, a heart rate of < 70 b/min during CTA was associated with a significantly improved specificity and PPV.

Feasibility of computed tomography perfusion in patients with chronic total occlusion undergoing percutaneous coronary intervention.

We aimed to establish the feasibility and safety of dynamic computed tomography perfusion (CTP) in patients with chronic total occlusion (CTO) undergoing percutaneous coronary intervention (PCI). Ten consecutive CTO patients with preserved left ventricular ejection fraction (≥50%) underwent regadenoson dynamic CTP prior to and at least 3 months after successful CTO recanalization. Quantitative absolute and indexed values of stress myocardial blood flow (MBF) were measured for each myocardial segment, and perfusion defect size was defined by the number of segments with indexed MBF ≤0.78. The control group comprised 10 subjects without ischemia on CTP. Out of 20 CTP studies with 320 segments, 311 segments (97.2%) were interpretable. The dose-length product for CTP was 589.5 â€‹± â€‹144.3 mGy cm, and no severe adverse reactions to either regadenoson or contrast were observed. Successful PCI resulted in a significant increase in stress MBF in CTO (101.8 [82.9-127.1] vs. 158.4 [132.6-172] ml/100ml/min, p â€‹= â€‹0.004). Overall, there were significant reductions in both CTO and total defect size post-PCI (5 [5-6] vs. 1 [0.3-2] and 6 [5-8.5] vs. 1.5 [1-3.8] segments, both p â€‹= â€‹0.002). In segment analysis, the indexed MBF was lowest in the pre-PCI CTO group (0.90 [0.53-1.0]), followed by post-PCI CTO group (0.96 [0.88-1.0]) and the control group (0.98 [0.94-1.0]). Dynamic CTP is feasible and safe, and shows large perfusion defects in patients with CTO. While ischemic burden can be significantly improved after successful CTO PCI, it is still larger as compared with normal myocardium. NCT04465526: The Influence of Coronary Chronic Total Occlusion on Myocardial Perfusion on Computed Tomography (COPACABANA).

Residual Quantitative Flow Ratio to Estimate Post-Percutaneous Coronary Intervention Fractional Flow Reserve.

OBJECTIVES: Quantitative flow ratio (QFR) computes fractional flow reserve (FFR) based on invasive coronary angiography (ICA). Residual QFR estimates post-percutaneous coronary intervention (PCI) FFR. This study sought to assess the relationship of residual QFR with post-PCI FFR. METHODS: Residual QFR analysis, using pre-PCI ICA, was attempted in 159 vessels with post-PCI FFR. QFR lesion location was matched with the PCI location to simulate the performed intervention and allow computation of residual QFR. A post-PCI FFR < 0.90 was used to define a suboptimal PCI result. RESULTS: Residual QFR computation was successful in 128 (81%) vessels. Median residual QFR was higher than post-PCI FFR (0.96 Q1-Q3: 0.91-0.99 vs. 0.91 Q1-Q3: 0.86-0.96, p < 0.001). A significant correlation and agreement were observed between residual QFR and post-PCI FFR (R = 0.56 and intraclass correlation coefficient = 0.47, p < 0.001 for both). Following PCI, an FFR < 0.90 was observed in 54 (42%) vessels. Specificity, positive predictive value, sensitivity, and negative predictive value of residual QFR for assessment of the PCI result were 96% (95% confidence interval (CI): 87-99%), 89% (95% CI: 72-96%), 44% (95% CI: 31-59%), and 70% (95% CI: 65-75%), respectively. Residual QFR had an accuracy of 74% (95% CI: 66-82%) and an area under the receiver operating characteristic curve of 0.79 (95% CI: 0.71-0.86). CONCLUSIONS: A significant correlation and agreement between residual QFR and post-PCI FFR were observed. Residual QFR ≥ 0.90 did not necessarily commensurate with a satisfactory PCI (post-PCI FFR ≥ 0.90). In contrast, residual QFR exhibited a high specificity for prediction of a suboptimal PCI result.

Functional recovery after percutaneous revascularization of coronary chronic total occlusions: insights from cardiac magnetic resonance tissue tracking.

To evaluate the effect of percutaneous coronary intervention (PCI) of coronary chronic total occlusions (CTOs) on left ventricular (LV) strain assessed using cardiac magnetic resonance (CMR) tissue tracking. In 150 patients with a CTO, longitudinal (LS), radial (RS) and circumferential shortening (CS) were determined using CMR tissue tracking before and 3 months after successful PCI. In patients with impaired LV strain at baseline, global LS (10.9 ± 2.4% vs 11.6 ± 2.8%; P = 0.006), CS (11.3 ± 2.9% vs 12.0 ± 3.5%; P = 0.002) and RS (15.8 ± 4.9% vs 17.4 ± 6.6%; P = 0.001) improved after revascularization of the CTO, albeit to a small, clinically irrelevant, extent. Strain improvement was inversely related to the extent of scar, even after correcting for baseline strain (B = - 0.05; P = 0.008 for GLS, B = - 0.06; P = 0.016 for GCS, B = - 0.13; P = 0.017 for GRS). In the vascular territory of the CTO, dysfunctional segments showed minor improvement in both CS (10.8 [6.9 to 13.3] % vs 11.9 [8.1 to 15.0] %; P < 0.001) and RS (14.2 [8.4 to 18.7] % vs 16.0 [9.9 to 21.8] %; P < 0.001) after PCI. Percutaneous revascularization of CTOs does not lead to a clinically relevant improvement of LV function, even in the subgroup of patients and segments most likely to benefit from revascularization (i.e. LV dysfunction at baseline and no or limited myocardial scar).